CHAPTER XI 



Order NEUROPTERA* 



The Horned Corydalus, the Laceiving-Flies, the Ant-Ltons, 

 and others 



The members of this order have four wings; these are membranous 

 and are usually furnished with many veins and cross-veins. In most 

 members of the order, the wings have been specialized by the addition in 

 the preanal area of many supernumerary veins of the accessory type. 

 The mouth-parts are formed for chewing. The tarsi are five-jointed. 

 The cerci are absent. The metamorphosis is complete. 



The order Neuroptera as now restricted differs greatly in extent 

 from the Neuroptera of the early entomologists. Formerly there were 

 included in this order many insects that are no longer believed to be 

 closely related. This has resulted in the establishment of several dis- 

 tinct orders for the insects that have been removed from the old 

 order Neuroptera. This fact should be kept in mind when consulting 

 the older text -books. 



The wings of the Neuroptera are membranous and usually fur- 

 nished with many wing-veins. The two pairs of wings are similar 

 in texture and usually in outline ; in some the fore wings are slightly 

 larger than the hind wings, in others the two pairs of wings are of the 

 same size. The anal area is small in both fore and hind wings ; it is 

 rarely folded (Sialidae), and then only slightly so. A distinct anal 

 furrow is rarely developed. Definitive accessory veins are usually 

 present, and, as a rule, there are many marginal accessory veins. 

 Intercalary veins are never developed. When at rest, with few ex- 

 ceptions, the wings are folded roof-like over the abdomen. In some 

 cases organs for uniting the fore and hind wings are present. 



Correlated with the extensive development of accessory veins in 

 the Neuroptera, there has resulted in nearly all of the families of this 

 order the production of a pectinately branched radial sector; that is, 

 this vein is so modified that it consists of a supporting stem upon 

 which are borne a greater or less number of parallel branches. This 

 is shown in most of the figures of wings illustrating this chapter, 

 and is a distinctive characteristic of this order; in no one of the 

 other orders of living insects in which accessory veins occur is a well- 

 developed pectinately branched radial sector found. Such a radial 

 sector existed, however, in many of the Paleozoic insects. In certain 

 genera of the Neuroptera a dichotomously branched radial sector has 

 been retained. 



In many Neuroptera one or more series of cross-veins extend 

 across the wing and form with sections of the longitudinal veins that 

 *Nenr6ptera: neuron (vevpov), a nerve; pteron {irrep6v), a wing. 



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